1. Field of the Invention
The present invention relates generally to the fields of medical physics and drug delivery. More specifically, the present invention relates to catheter devices for delivering electromagnetic energy to enhance permeation of substances.
2. Description of the Related Art
The human body is composed of a variety of passageways including blood vessels, intestines, urinary passages, etc. These passageways may, at times, provide unique access to surrounding tissues and organs. For example, the prostate gland is located anatomically in a position that is juxtaposed to the colon and bladder. Thus, by traversing the membranes of the colon or bladder, direct local access to the prostate and surrounding tissue is possible. In this way, these body passageways become a route for local delivery of substances.
At other times these passageways may be the site of abnormal growths which cause obstructions and other problems. As a result, tissues and organs beyond these obstructions may be starved for nutrients. Alternatively, the obstructions may prevent drainage of waste materials. Some growths such as tumors may ultimately starve the surrounding tissues or produce toxic substances themselves. Thus, the effects of these obstructions may ultimately lead to toxicity and even death.
Cells and materials which commonly form obstructions are capable of being dissolved or removed by various chemical agents. Nevertheless, achieving effective concentrations of these agents systemically is very difficult as they are often toxic in large doses or have serious side effects. For example, the clot dissolving agent Tissue Plasminogen Activator (TPA) is effective at dissolving the kind of blood clots found in coronary restenosis or in deep vein thrombosis (DVT). However, when administered systemically in doses great enough to affect regions of the heart or distal venous regions of the leg, the drugs cause side effects which can lead to hemorrhage or other forms of internal bleeding. Thus, it is desirable to deliver high concentrations of TPA to local regions of the heart or venous portions of the leg without affecting distal and surrounding tissues and organs.
The prior art is deficient in the lack of effective means of delivering non-ionizing electromagnetic energy for enhancing drug delivery. The present invention fulfills this long-standing need and desire in the art.
The present invention describes multi-lumen catheter devices which are capable of delivering high concentrations of pharmaceutically active substances and varying types of electromagnetic energy to a selected site. As a result, the electromagnetic energy enhances the local tissue distribution of the active substance and improves the permeation of the substance into cells and tissues. These devices allow high concentrations to be delivered locally, however, when diluted by the body""s fluid volume, the ultimate concentration delivered to distal tissue is extremely small. The high local concentration allows for greater efficacy in treatment, while the low distal concentration minimizes toxic or other unwanted effects in tissues that are not the target of the treatment.
The present invention relates to therapeutic treatments of blood vessels and other body passages and tissues that may be accessed through the body""s passageways. The present invention further provides a device that delivers electromagnetic energy, along with a pharmaceutically active substance, to the site of therapy. By doing so, delivery of the active substance is enhanced. High local concentrations of a therapeutic substance is delivered to a target, which, if delivered systemically, would not be desirable due to systemic toxicity and other effects.
In one embodiment of the present invention, there is provided a catheter device for enhancing local delivery of a compound in a subject, said catheter comprising a first lumen for delivering electromagnetic energy to the subject; a second lumen for delivering the compound to the subject; a proximal end; and a distal end. Preferably, the proximal end comprises fiber optic attached to a source of electromagnetic energy; and a connection through which the compound is delivered into the second lumen. The distal end comprises a port through which the compound is delivered to the subject; and an optics assembly for transmitting the electromagnetic energy to the subject, wherein the optics assembly comprising an optic probe with a tip. Optionally, the catheter device further comprises a means to observe the placement of the tip, such as endoscope.
In another embodiment of the present invention, there is provided a catheter device for enhancing local delivery of a compound to a site of interest in a vascular vessel, comprising a first lumen for delivering electromagnetic energy to the site; a second lumen for delivering the compound to the site; and two inflatable chambers located on either side of the site, wherein a space is created between the two chambers. Preferably, the chambers are filled with Theological material. Optionally, the vascular vessel catheter device further comprising laser chips to be placed into the vascular vessel.
In still another embodiment of the present invention, there is provided a catheter device for enhancing local delivery of a compound to a body cavity, comprising a first lumen for delivering electromagnetic energy to the site; a second lumen for delivering the compound to the site; and single or multiple inflatable chambers filled with rheological material, wherein the chambers are placed in the cavity. An example of the body cavity is bladder.
In yet another embodiment of the present invention, there is provided a method for enhancing local delivery of a pharmaceutical compound to a subject, comprising the steps of irradiating the subject with electromagnetic energy and administering the pharmaceutical compound to the subject, wherein both the electromagnetic energy and the pharmaceutical compound is delivered through the catheter device disclosed herein.
In still yet another embodiment of the present invention, there is provided a method for increasing the diffusion rate of a substance in a medium, comprising the step of applying electromagnetic energy to the medium, wherein the electromagnetic energy generates propagating pressure wave upon the medium, and wherein the electromagnetic energy is delivered through the catheter device disclosed herein.
In still yet another embodiment of the present invention, there is provided a method for improving permeation rate of a molecule through a barrier, comprising the step of applying electromagnetic energy to the barrier, wherein the electromagnetic energy is delivered through the catheter device disclosed herein, and wherein the electromagnetic energy ablates or alters the structure of the barrier.
In still yet another embodiment of the present invention, there is provided a method for creating pores in a barrier thereby improving permeation rate of a molecule through the barrier, comprising the step of applying electromagnetic energy to the barrier, wherein the electromagnetic energy is delivered through the catheter device of disclosed herein.
The method disclosed herein may be used for treating a disease in a vascular vessel, a body cavity or other body passage.
Other and further aspects, features, and advantages of the present invention will be apparent from the following description of the presently preferred embodiments of the invention given for the purpose of disclosure.